B. Accidents
S 912-022-N00
(1) Pratt & Whitney considers engines and engine parts involved in the following types of accidents potentially acceptable or continued aircraft usage:
(a)
Engines and engine parts installed in an accident in which the nacelles and engines remain undamaged.
(b)
Engines and engine parts involved in a fire wherein a portion of the aircraft was destroyed but the engines were not subjected to fire damage.
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(c)
Engines and engine parts involved in an accident wherein engines rotate freely, although impact damage to cases or other engine parts is evident.
(d)
Partially damaged engines which will not rotate freely as a result of superficial damage to cases, etc.
(e)
Engines subjected to partial or full immersion in fresh or salt water for a brief period of time.
S 912-023-N00
(2) Acceptance criteria for engines and engine parts which are involved in the types of accidents listed above:
(a)
Engines and engine parts involved in accidents described in steps A.(1).(a) and A.(1).(b) can be considered "not involved"
______________ in an abnormal operational circumstance.
(b)
Engines and engine parts involved in accidents described in steps A.(1).(c), A.(1).(d) and A.(1).(e) should be 100 percent disassembled and inspected.
NOTE: Owners who are unable to perform the necessary tests or
____ who are in doubt whether to accept or reject a part should contact Pratt & Whitney for assistance.
TASK 70-00-02-912-024-N00
4. Serious Operational Events
__________________________
A. Access
(1)
Location Zones
412 No. 1 Power Plant
422 No. 2 Power Plant
432 No. 3 Power Plant
442 No. 4 Power Plant
B.
Procedure
S 912-025-N00
(1) Pratt & Whitney considers engines and engine parts involved in the following types of serious operational events as potentially acceptable for continued aircraft usage provided the criteria defined are observed.
(a) Single fan blade fractures outboard of part span shroud.
NOTE: A single fan blade fracture occurring outboard of the
____ part span shroud can cause varying degrees of engine damage. Refer to respective model engine manual for bird or object ingestion inspections and damage limits. In general, the following inspection guidelines can be applied to events where a single blade has fractured outboard of the part span shroud.
1) Check for evidence of core ingestion.
2) Inspect fan blade shrouds for evidence of shingling.
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3) Inspect fan rubstrip for damage beyond limits.
4) Check fan exit guide vanes for damage.
5) Inspect engine externals for broken or cracked brackets and
case flanges.
6) Borescope inspect compressor gaspath for excessive blade tip rub and blade-to-vane clash.
7) Single blade fracture inboard of part span shroud or multiple fan blade fractures.
NOTE: A fan blade fracture inboard of the part span shroud
____ or multiple fractures generate a significant amount of rotor vibration. More extensive inspections with disassembly of the N1 rotor modules is required as a minimum. Further teardown is required as inspection findings dictate.
(b)
Engines experiencing sudden stoppage.
1) Engines experiencing sudden stoppage usually as a result of significant ingestion or distress. In every instance of sudden stoppage, a complete engine teardown and 100 percent engine part inspection should be accomplished.
(c)
Engines involved in an operational fire (burn-through, bearing compartment, etc.). 1) Engines involved in an operational fire should be
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